Flexible blasting mat



July 18, 1967 L. BELANGER 3,331,322

FLEXIBLE BLASTING MAT Filed Oct. 22, 1965 2 Sheets-Sheet 1 INVENTOR LIONEL BELA/VGER ATTORNEY? y 18, 1957 L. BELANGER 3,331,322

FLEXIBLE BLASTING MAT Filed 001,. 22, 1965 2 Sheets-Sheet 2 INVENTOR LIONEL BELA/VGER "ATTORNEY United States Patent Orifice 3,331,322 FLEXBLE BLASTING MAT Lionel Belanger, 3021 Lakeshore Road, Burlington, Ontario, Canada Filed Oct. 22, 1965, Ser. No. 502,216 3 Claims. (Cl. 102-22) ABSTRACT OF THE DISCLOSURE This specification discloses a flexible blasting mat comprising a plurality of wire rope U-shaped loops in longitudinally spaced relation presenting spaced sides on which are threaded rubber tire sections in overlapped, interleaved relation providing identical opposed mat faces together with end plates that are also threaded on the ropes. The ropes of the end loops are continued out and returned back on one side to provide means for accommodating the hook of a hoist.

This invention relates to a blasting mat formed of scrap rubber.

Blasting mats such as are used in excavation and the like have generally speaking in the past been made of heavy rigid material such as wooden blocks or heavy girders -or the like. Such rigid materials tended to offer unyielding resistance to blasting and explosive forces and, Where such explosive forces were excessive due, possibly to use of more blasting powder than was necessary for the job, then the mats have become broken and require repair. In addition, the problem of handling such heavy rigid articles is aggravated by the fact that greatly excessive weight must be provided in order to give them adequate strength for the purpose. In addition, the type of materials used in such blasting mats are relatively expensive and the cost thereof was in many cases uneconomic.

Some crude attempts have been made to provide a flexible blasting mat utilizing scrap material such as rubber but generally speaking they have failed to incorporate suflicient weight in a given area of mat to function effectively. In addition, the construction has been flimsy and has resulted in frequent breakages requiring repair or rendering the mats useless.

Accordingly, it is an objective of the present invention to provide a blasting mat which is made of scrap rubber material, preferably from automobile and truck tires which incorporates substantial weight for a given area of mat, which is of strong rugged construction and which is, at the same time, sufiiciently flexible to yield to excessive blasting forces without rupturing the mat.

More particularly, it is an objective of the present invention to provide a blasting mat having the foregoing advantages in which both faces of the mat may be used to an equal extent without risking damage to the mat.

More particularly, it is an objective of the present invention to provide a blasting mat having the foregoing advantages in which the resiliency of the rubber material is utilized to provide increasing shock absorption thereby considerably reducing the strains applied to the other portions of the mat.

More particularly, it is an objective of the present invention to provide a method of making a blasting mat having the foregoing advantages in an improved manner.

The foregoing and other objective will become apparent from the following description of a preferred embodiment of the invention which is here given by way of example only, with reference to the following drawings in which like reference devices refer to like parts thereof the various views and diagrams and in which:

FIGURE 1 is a perspective illustration of an automo- 3,331,322 Patented July 18, 1967 bile tire showing the manner in which it may be made available for use in a blasting mat according to the invention;

FIGURE 2 is a plan view of one side of a blasting mat according to the invention with the central portion thereof omitted for the sake of clarity and showing the arrangement of the parts therein;

FIGURE 3 is a section along the line 3-3 of FIG- URE 2;

FIGURE 4 is a section along the line 4-4 of FIG- URE 3;

FIGURE 5 is a section along the line 55 of FIG- URE l; and

FIGURE 6 is a schematic plan view of a method of assembling a blasting mat according to this invention.

For the purposes of the following explanation, FIG- URE 1 shows an automobile tire which provides the raw material for the construction of the mat. It will be noted from FIGURE 1 that the automobile tire indicated generally as T is cut into six segments each segment being indicated as S. These six segments are formed by first of all cutting the tire transversely in section in three cuts spaced apart therearound, by These cuts being indicated as C1. These three equal arcuate segments are then each divided longitudinally to two half segments by cutting the same longitudinally along the middle of the tread portion along the line indicated as C2. Each such half segment 10 will then consist of a portion of sidewall and a half portion of tread. The sidewall portions of each half segment 10 are then punched to provide two holes indicated as 11.

The completed blasting mat as shown in FIGURES 2, 3, and 4 consists of a large number of the half segments 14) threaded in overlapping relation on flexible wire rope loops 12 passing through holes 11 therein. It will be noted that in the example shown there are four separate ropes 12 indicated as 12a, 12b, 12c and 12d each such rope being doubled over and passing through holes 11 in one complete column of segments 10 and also through the holes 11 of one side only of the next adjacent column of segments 10, the segments 10 of adjacent columns overlapping one another and being interleaved one above the other on such a rope 12. In this way, a continuous mat is provided, in this case having seven distinct columns of segments 10 overlapping and interleaved with one another. In addition, it will be noted that in this preferred embodiment of the invention, both working surfaces of the mat are identical, this being achieved by means of providing each such column of segments 10 consisting of pairs of segments 10 arranged with their respective tread portions 13 being directed to opposite respective faces of the mat as shown in FIGURES 3 and 4. In this way, the available weight of the mat is very considerably increased in relation to its area and in addition, the resiliency of the segments 10 tends to resist the separation of ropes 12 under blasting pressures thereby providing considerable shock absorption to the mat and lengthening its useful life.

The attachment of ropes 12 and fastening the same in position is provided by means of a series of overlapping end plates 14 and provided with holes 15 therein through which ropes 12 pass, the spacing of holes 15 corresponding to the spacing between holes 11 in segments 10. In this way, top and bottom edges of the mat permit flexing of the mat transversely to its plane but resist stretching of the mat parallel to its plane thereby increasing the resistance to the blasting forces. The upper edge of the mat is further strengthened and provided with lifting means by providing endwise extensions of ropes 12 which are then carried along the upper edge of the mat in overlapping relation. Thus the outermost portions of ropes 12a and 12d are extended and carried across the full length of the upper edge of the mat in overlapping relation and are tied together by means of clamps 16. The ends of the ropes 12band 120 are clamped to the endwise extensions of ropes 12a and 12b by means of similar clamps 16. In addition, a reinforcing type rope 17 extends along the full length of the upper edge of the mat and being clamped to ropes 12a, 12b, 12c and 12d by means of further clamps 16 thereby providing a three ply thickness of rope to define a lifting loop 18 for reception of the hook of a crane or other lifting device.

According to this preferred embodiment of the invention, the instant blasting mat is preferably manufactured by use of substantial compression. The rubber segments being deformable from their predetermined shape corresponding to a portion of a tire are capable of substantial compression and upon such compression will occupy a substantially smaller space thereby increasing the available weight of the mat and at the same time will incorporate a considerably greater degree of resiliency for resistance to explosive forces. Accordingly, the invention preferably provides for a method of manufacture of such blasting mat which will be described in relation to FIGURE 6. From FIGURE 6 it will be noted that according to the method of the invention, the series of four ropes 12, indicated as 12a, 12b, 12c and 12d are arranged side by side in U-shaped loops on a floor or other working surface and the free ends are anchored in any suitable releasable clamping mechanism indicated as 20, Workmen will then release the ends of the ropes 12 in sequence and thread them through holes 11 in tire segments 10 and push the tire segments 10 down towards the bight or loop in the respective ropes, interleaved the one with the other in the manner described upon so as to produce interlocking segments 10 interleaved with one another and having upwardly and downwardly directed faces. After some ten or fifteen courses of segment 10 have been accumulated on ropes 12, all of the free ends of ropes 12 are then anchored once again in clamping mechanism 20 and a compression bar or comb member 21 is introduced between ropes 12 and is drawn firmly down towards the loops of ropes 12 ino contact with the segments 10 threaded on ropes 12 and then substantial tractive pressure is applied to comb member 21 by means of, for example, yoke 22 and tackle 23. After the segments 10 have been compressed to a sufficient degree, the tractive force is released and the comb 21 is drawn away from segments 10 and threading of segments 10 onto ropes 12 may be resumed for a further ten or fifteen courses after which further pressure is applied.

The foregoing is a description of a preferred embodiment of the invention which is here made by way of example only. The invention is not to be taken as limited to the specific steps described but comprehends all such variations as come within the spirit and scope of the appended claims.

What I claim is:

1. A blasting mat comprising a plurality of U-shaped loops of wire rope in longitudinally spaced relation with each loop having a pair of spaced parallel sides, all of said sides being spaced uniformly apart; a plurality of arcuate tire segments of substantially the same size and shape and each consisting of one half the tread portion of the tire from which it was formed and a side wall portion having a hole in each end thereof; each of said loops carrying a plurality of said segments and each pair of the sides of adjacent loops carrying a plurality of said segments with the sides of the loop being threaded through said openings and the segments on each loop being interleaved with the segments on the adjacent pair of sides, and with the tread portions of the segments on each loop and pairs of sides being in a compact overlapped relation; said segments being alternately arranged whereby the tread portions of adjacent segments assume positions on opposite faces of the mat and end plates at each end of each loop and pair of sides with said end plates having openings receiving the sides of the respective loops.

2. The blasting mat of claim 1 together with a lifting loop at one end of the mat and connected to said wire ropes.

3. The blasting mat of claim 1 in which said arcuate segments have an extent of References Cited UNITED STATES PATENTS 2,926,605 3/1960 Hammel et al. 102-22 FOREIGN PATENTS 120,935 2/ 1948 Sweden. 139,965 4/1953 Sweden. 162,718 4/1958 Sweden.

BENJAMIN A. BORCHELT, Primary Examiner.

SAMUEL FEINBERG, Examiner.

V. R. PENDEGRASS, Assistant Examiner. 

1. A BLASTING MAT COMPRISING A PLURALITY OF U-SHAPED LOOPS OF WIRE ROPE IN LONGITUDINALLY SPACED RELATION WITH EACH LOOP HAVING A PAIR OF SPACED PARALLEL SIDES, ALL OF SAID SIDES BEING SPACED UNIFORMLY APART; A PLURALITY OF ARCUATE TIRE SEGMENTS OF SUBSTANTIALLY THE SAME SIZE AND SHAPE AND EACH CONSISTING OF ONE HALF THE TREAD PORTION OF THE TIRE FROM WHICH IT WAS FORMED AND A SIDE WALL PORTION HAVING A HOLE IN EACH END THEREOF; EACH OF SAID LOOPS CARRYING A PLURALITY OF SAID SEGMENTS AND EACH PAIR OF THE SIDES OF ADJACENT LOOPS CARRYING A PLURALITY OF SAID SEGMENTS WITH THE SIDES OF THE LOOP BEING THREADED THROUGH SAID OPENINGS AND THE SEGMENTS ON EACH LOOP BEING INTERLEAVED WITH THE SEGMENTS ON THE ADJACENT PAIR OF SIDES, AND WITH THE TREAD PORTIONS OF THE SEGMENTS ON EACH LOOP AND PAIRS OF SIDES BEING IN A COMPACT OVERLAPPED RELATION; SAID SEGMENTS BEING ALTERNATELY ARRANGED WHEREBY THE TREAD PORTIONS OF ADJACENT SEGMENTS ASSUME POSITIONS ON OPPOSITE FACES OF THE MAT AND END PLATES AT EACH END OF EACH LOOP AND PAIR OF SIDES WITH SAID END PLATES HAVING OPENINGS RECEIVING THE SIDES OF THE RESPECTIVE LOOPS. 